Smelting-furnace.



G. A. WETTENGEL. SMELTING 'FURNAGH APPLICATION FILED AUG. I3. 1907.

Patented Oct. 20, 1908.

2 SHEETS-SHEET 1.

f. m. M T

GL A. WETTENGEL.

SMELTING FURNACE.

APPLICATION FILED AUGlls. 1907.

Patented Oct. 20, 1908` 2 SHEETS-SHEET 2 GEORGE ALEXANDER WETTENGEL, 0F ST. LOUIS, MISSOURI.

SME LTING-FURNACE Specification of Letters Patent.

Patented Oct. 20, 1908.

Applicatign led August 13, 1907. Serial No. 388,325.

To all whom 'it may concern:

Be it known that I, GEORGE ALEXANDER WETTENGEL, a citizen of the United States, residing in the city of St. Louis and State of Missouri, have invented certain new and useful Improvements in Smeltin0'-Furnaces, of which the following is a specication.

This invention relates to certain new and useful improvements in smelting furnaces, and the object is to provide a rotatable smelting furnace to facilitate charging the ore into the retorts, discharging the residue after smelting, and recovering the metal from the ore smelted therein.

The peculiarities of my invention will be hereinafter pointed out and claimed.

In the accompanying drawings in which like reference letters indicate corresponding parts, Figure l represents a front\v1ew of a smelting furnace, illustrating my invention with parts in section; and Fig. 2, a vertical cross section on the line X--X of Fig. 1.

I will describe my invention as applied to the smelting of zinc ore to which it is especially adapted, but it is not limited to this particular ore. The common method of smelting zinc ore is to mix it with a reducing agent, usually coal in suitable proportions, pack this mixture into suitable retorts of fire clay slightly inclined from the horizontal in a furnace, and vsubject the retorts to the heat of burning gas to smelt t-he ore and vaporize the zinc,which is condensed to the liquid form of molten zinc'and drawn off at suitable intervals. These retorts, A, are about 4 feet long, 8 inches internal diameter and l inches thick, closed at the rear, and supported at both, ends in rows separately from each other, on a tile shelf at the front and rear of the furnace, to allow the burning gas to lay on all sides of them. Their 'front en s are left open, to allow of shoveling in the charge, and are then closed by the conical tubes, B, constituting the condensers, which extend `beyond the furnace proper, and are cach'supported by a pivoted frame, `C. The spaces tween the retorts at the fronts are closed with fire clay, the joints between the retorts and condensers are made-ti ht with loam and the small end of the con enser closed and vented. The vapor of zinc from the smelting ore is liquefied in the condensers, B, from which it is drawn into a trough, D, at about eight Vhour intervals, (or three times in 2O hours),

after which the retorts are cleaned out and recharged. The cleaning of the retorts is hard labor because of the heat kand dirt. It requires much labor and considerable skill to shovel the ore mixture in'to the retorts in the common construction of smelting fur'- nace.

In my construction the furnace, E, of fire brick, or other suitable material, forms thc lining of a cylindrical metal drum, F, of any convenient length, and the retorts are mounted therein in the usual, or any suitable manner. Strong metal rings, G, encircle the drum at suitable intervals, and preferably support the furnace on rollers, H, mounted in suitable bearings, so that the furnace can be rotated by operating the pinionyl'; meshing with the master gear, J, or otherwise. One roller'is flanged and the other plain, to allow for expansion.

The furnace is supplied with air and gas, entering through sultable openings, K, preferably 1n the rear wall, the top and the bottom of the drum. The air pipes, L, extend along the outslde of the drum, and are conveniently supported by the track rings, G, (or otherwise mounted so as to turn with the furnace), and are united at one end by an inlet pipe, M, Fig. l, located axially with the track rings, G, and making a suitable rotatable oint with the blast fan outlet, N.

The gas pipe, P, Fig. 2, makes a similar axial joint with the end, Q, of the gas supply pipe, R, as shown. Branch pipes with regulating valves connect the air and gas pipes respectively, with the said inlet openings, K. Thus the furnace can be properly heated and rotated, and the air and gas regulated in any rotated position.

Above the furnace is a traveling crane, S, carryin a hopper'trolley T, rovided with slide-va ve openings, t, mato ing the vertical rowsof retorts, Fig. 1, when the furnace is rotated so that the front is upward. The crane andV trolley can, therefore, readily charge the retorts from the supply hopper, U. The retorts, bein on end when in charging position, can le completely filled; then the furnace is rotated downward to the right or left through one-quarter turn and the retorts brought nearly toa horizontal to the top by about one-third revolution of slightly, while the lower side of the con- V, mounted on carrying wheels, receives the molten metal from the trough, D.

In a furnace of the ordinary construction, the retorts are cleaned ofresidue by taking ofl" the condensers, inserting along pipe nozzle with a perforated end through which a small quantityof water is delivered to the back of the retort chambers successively. The steam that immediately forms blows out the powderlike residue by its expansion in changing from a liquid to a aseous form. A portion of zinc ore mixture orms a sticky slag on the bottom that can only be partly removed by laborious scraping. This slag accumulates and reduces the size and efflciency ofthe retort and nally cuts holes clear through the retort, thereby necessitating its being replaced. Inmy rotatable furnace, the condensers are taken off, and then the furnace is* turned downward till the mouths of the retorts are over the pit, W, into which the loose residue is discharged from all retorts simultaneously.` The cooling action of the water is done awaywith and .the consequent injury to the red'hot retorts. Then the retorts are brought to an inclined position and the loam and any-remaining residue are scraped out; the furnace is then revolvedpuntil the retorts stand vertical with the open ends up, being brought the furnace, the recharging is effected as before described, and the furnace is`rotated a quarter`turn, but with` the front facing the opposite side, thereby bringin the slag residue uppermost in the retort c amber, .where it will melt and dri down onthe smelting charge and go out into the it on the next discharge. This reversal o the retorts in my furnace makes them practicallyl selfcleaning, almost entirely avoids scraping, and increases the life of the retorts by using tw'o sides of the retort so that the slag cannot melt holes into it as easily as in the ordinary construction.

The average life of a retort is about thirty days During that time it absorbs about 25 lbs. of zinc; but this .absorption takes placealmost entirely during therst week of its use, and decreases in daily quantity as the.

retort gets older. Therefore, the longer the life of the retorts, the greater the output of the furnace, and the greater the 4percentage of metal recovered becomes, compared with the quantity of metal in the ore, `since they have. taken up lnearly their load of metal during the first week of use. p

My rotatable furnace, withits self-cleaning and effective retorts, has a larger eiliciency than the old form.

The temporary trough, D, is taken oil' before rotating. The track ring is preferably eccentric as to thel drum, to avoid making the rin so much larger and yet embrace the gas an air`pipes. The gas and air supply to each burner can be regulated as may be necessary, inorder to maintain the temperature as required at different times during the smelting operation.

It will be understood that ymy rotatable furnace can also beused fqr -smelting other metals than zinc, such as quicksilver ore, and it is also applicable to the manufacture of coal gas.

Having thus fully described my invention, what I claim as new and desire to se, cure by Letters Patent is:

1. A rotatable smelting furnace having a series of retorts transversely placed in a cylindrical drum, and adapted to rotate the open ends of the retorts upward for chargin A rotatable smelting furnace comprising a suitable rotatable casing=and a series of retorts transversely mounted therein, whereby said retorts may be turned downward for discharging.

3. A rotatable smelting furnace having retorts adapted to be reversed for self-cleaning, substantially as described.

4. A rotatable smelting furnace having retorts horizontally disposed, and regulated flame openings at the rear and above and below, for securing equal elciency in either rotated osition. 5. rotatable smelting furnace having retorts in rows adapted to be turned upward for charging, in combination with a traveling hopper having re lated openings matching said retorts, su stantially as de-t scribed.

6. A rotatable smelting furnace having retorts in rows adapted to be turned upward for chargin in combination with an 'overhead trave g crane, a trolley ho per mounted thereon, andhaving regu ated p openings matchin said retorts, and a main hopper for supp ying said trolley hopper with chargin mlxture.

7. A rotata le smelting furnace having retorts transversely disposed in a cylindrical drum, gas and air pipes carried by said drum and having practically concentric axial inlets, and means tol rotate said fur'- nace.

' air pipes having inlets concentric wlth said 8. A rotatable smelting furnace compristrack rings and connected with lamzeopen- In testimony whereof I have ffixed my ings sald drilm, sulstantifally as'"'dle'seribed. signature in presence of two witnesses.

9. rotate e sme tin urnace mvn a l yseries of retorts, adaptedgto be rotated sogas GEORGE ALEXANDER WETTENGEI" 5 to invert the retorts, whereby the bottom ofA Witnesses:

each retort maybe made to serve as the top, Enw. J. HAUSGHULTE, and Vice versa. i WM. A. MANHART. 

